“…High pure deuterium (D 2 ) is an important industrial and scientific gas, which has been widely used as an irreplaceable raw material, neutron moderator, isotopic tracer, and in other fields. Extraction of D 2 from its isotopic mixtures can create tremendous economic value and is of industrial importance for many fields, including medicinal chemistry, environmental studies, and nuclear power. − Despite the huge demand for it, the mole fraction of natural deuterium is only up to 0.0156% of natural hydrogen in the oceans . Moreover, D 2 and its isotope (H 2 or T 2 ) molecules have almost identical classical dimensions of 2.4 Å × 2.4 Å × 3.14 Å, associated with very similar physicochemical properties (especially, boiling points: H 2 , 20.39 K; D 2 , 23.67 K; T 2 , 25.03 K), and the separation of hydrogen isotope mixtures in high purity has been considered as one of the greatest difficulties and challenges in modern separation technology .…”